I Want to Mix the Value Together.

When I check all the checkboxes and choose 1 to 10 in the combobox, which is the quantity of an item based on how much I want it displays on the side of the label, for example: hawaiian pizza cost for 200, pepperoni pizza cost for 100, then it did display on the label which is 300, then if I choose 2 items in hawaiian, since I only have 1 and I want to make it 2 pizza, it didn’t calculate. I tried to fix it, and it works, but its display on the side of the label like this: $300.00, $600.00 — the problem is I can’t mix them together. Hopefully, someone can help me again.